Question

question 28
the reticular activating system maintains
sleep rhythms.
consciousness.
unconsciousness.
sensory impulses.
question 29
axon terminals of autonomic neurons release either of two neurotransmitters,
norepinephrine and acetylcholine.
norepinephrine and aldosterone.
norepinephrine and dopamine.
acetylcholine and aldosterone.
question 30
which region of the brain plays a part in the mechanism responsible for emotions by associating sensory impulses with feelings of pleasantness and unpleasantness?
hypothalamus
pineal gland
thalamus
pons

Explanation:

• Question 28: The reticular activating system (RAS) is a network of neurons in the brainstem. Its main function is to regulate consciousness. It filters sensory information and determines what reaches the conscious mind. Sleep rhythms are more associated with the suprachiasmatic nucleus and circadian - related mechanisms. Unconsciousness is the opposite of what the RAS promotes. Sensory impulses are processed by various parts of the nervous system, but the RAS's key role is in consciousness.
• Question 29: Autonomic neurons (part of the autonomic nervous system) have axon terminals that release neurotransmitters. The two main neurotransmitters are norepinephrine (released by sympathetic post - ganglionic neurons in most cases) and acetylcholine (released by parasympathetic post - ganglionic neurons and sympathetic pre - ganglionic neurons). Aldosterone is a hormone (mineralocorticoid) produced by the adrenal cortex, not a neurotransmitter. Dopamine is mainly associated with the central nervous system's reward pathways and other functions in the brain, not as a primary autonomic neurotransmitter.
• Question 30: The hypothalamus is involved in emotional responses. It can associate sensory impulses with feelings of pleasantness and unpleasantness. It also has connections to the limbic system (which is crucial for emotions). The pineal gland is mainly involved in regulating sleep - wake cycles (through melatonin production). The thalamus is a sensory relay station. The pons is involved in functions like sleep, respiration, and balance, but not specifically in associating sensory impulses with emotional pleasantness/unpleasantness.

Answer:

• Question 28: consciousness.
• Question 29: norepinephrine and acetylcholine.
• Question 30: hypothalamus.